How To : motor to ax coupling
Romanian
When a stepper motor is inline with a screw thread ax then you can use a fixed coupling. But in practice it difficult to make this inline. So we need  flexible couplings.

1) Some people are using a Tube. I have no experience with this coupling type, but i think it’s not accurate enough to use it on an engraving machine.

flexible_tube_coupling

This picture is from www.marcocnc.com

This one is used on a foam cutter. I think that is ok because there is no or a little force needed for foam cutting.

2) A very smart coupling is made by Jaak Claesen ( see also on my “visitor experience page” )

hobby_cnc_engraving_machine_jaak_claesen_13k

It’s easy to make and you can replace the plastic part through a thin metal plate. About 0.1mm thickness.

3) Aluminum and nylon. The are easy to make and works good.

selfmade_ax_coupling

Nylon can absorb fluid and that’s nice. So heat up some thin oil and put the nylon in the oil. Than you have a self greasing coupling.

You can also buy this oiled nylon. ( I don’t know where but it is on the market )

selfmade_ax_coupling2_oil
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